21857811038 has 16 divisors (see below), whose sum is σ = 38762621280. Its totient is φ = 9044611296.

The previous prime is 21857810993. The next prime is 21857811061. The reversal of 21857811038 is 83011875812.

It is a self number, because there is not a number n which added to its sum of digits gives 21857811038.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26918081 + ... + 26918892.

It is an arithmetic number, because the mean of its divisors is an integer number (2422663830).

Almost surely, 2^21857811038 is an apocalyptic number.

21857811038 is a deficient number, since it is larger than the sum of its proper divisors (16904810242).

21857811038 is a wasteful number, since it uses less digits than its factorization.

21857811038 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53837011.

The product of its (nonzero) digits is 107520, while the sum is 44.

The spelling of 21857811038 in words is "twenty-one billion, eight hundred fifty-seven million, eight hundred eleven thousand, thirty-eight".